“The selfish-gene is blinding us.”

David Dobbs claims that “the selfish-gene model increasingly impoverishes both scientific and popular views of genetics and evolution.”

He’s totally right that gene expression has been (relatively) ignored in popular accounts of development/evolution. But there is nothing about our current understanding of gene expression that invalidates the “selfish gene” idea. In fact, gene expression is controlled by other genes, interacting with the environment. (e.g., water temperature can trigger sex changes in some species of amphibians) 

In addition, he completely ignores one of the founding principles of evolutionary bio as applied to humans and other social animals — Robert Trivers’ concept of reciprocal altruism. What Trivers says is: Selfish genes can create unselfish people. So, even if the gene is the basic unit of evolution, then we can still have morality, self-sacrifice, and all sorts of forms of noble human behavior.

It’s a false dichotomy to say that it’s one or the other.

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Daniel Kahnemann – “I see a train wreck looming.”

The Economist highlights the problems with peer review:

“Consider 1,000 hypotheses being tested of which just 100 are true (see chart). Studies with a power of 0.8 will find 80 of them, missing 20 because of false negatives. Of the 900 hypotheses that are wrong, 5%—that is, 45 of them—will look right because of type I errors. Add the false positives to the 80 true positives and you have 125 positive results, fully a third of which are specious. If you dropped the statistical power from 0.8 to 0.4, which would seem realistic for many fields, you would still have 45 false positives but only 40 true positives. More than half your positive results would be wrong.”

Kahnemann’s predicted crisis pertains to priming studies that purport to show a variety of small, almost unnoticeable environmental factors can have an impact on people’s behavior.  One of the best examples is the research that showed that a subject exposed to lots of words pertaining to old age (e.g., grey, slow, addled) would walk more slowly afterward, presumably because they were primed to act older.  (Hasn’t been replicated, btw.)

Russ Roberts also takes on the difficulties of deriving life tips from the peer reviewed literature in his discussion with Emily Oster about her book debunking many pregnancy myths.  As Russ points out, a p value < .05 says nothing about the size of the effect that was found.  (An extremely low p value might apply to an observed effect that is so small it has no implications for anything.)

And that’s on top of all the mathematical problems with the .05 threshold.

 

 

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Why do machines take bankers’ hours? So bankers can make more money.

Planet Money asks why it takes 5-7 business days to send money – which is a purely digital transaction – while we can now have diapers, books, and even appliances delivered to our door within 24 hours.

They conclude that the ACH money transfer system is “so slow because it was designed in the 1970’s.”

But the more interesting question is why hasn’t it been updated?  Are the financial institutions benefiting from this glacial system of ACH money transfers?  

At another point in the story, Alex Blumberg admits that he has paid lots of money in overdraft fees, due to transfers that didn’t go through as fast as he expected them to.

And the banks won’t answer any questions about ACH.

And then the other shoe drops. They reveal that the banks have voted down potential upgrades out of fear that a faster ACH system will cannibalize other forms of transfers, like wires, that are fast but expensive. So this is good old-fashioned collusion.

 

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“You’re gonna pay for it down the line.”

Frontline takes on the NFL over concussions.

Knowing what we do about the brain, it’s hard to imagine that repeated traumatic impacts to the head wouldn’t have some negative effect over time.  And it’s obviously not hard to imagine that the NFL would go to extreme lengths to avoid admitting this, given the money involved.

But the rigor of the reporting isn’t quite what you’d expect from Frontline.  For one thing, they don’t even bring up the problems with correlation.  In other words, just because NFL players suffer from chronic traumatic encephalopathy (CTE), it doesn’t mean that playing in the NFL caused the disease.

Of course, it’s reasonable to think that it might have.

But NFL players are the definition of a non-random sample, extreme in almost every sense of the word.  What if higher levels of testosterone cause CTE?  Or use of PEDs?  Or forced retirement in your mid-30’s?  Or some other trait that many NFLers share?

I don’t know how you do this story without raising that issue.

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Do investment returns decrease…as society becomes wealthier?

William Bernstein – in the Financial Analysts Journal – claims that investment returns decrease as society becomes wealthier.

I stumbled over this.  Why would that be?  

But he makes a compelling case.  When we talk about investment returns from the POV of the user of the capital, we talk about the “cost of capital.”  This is what we have to pay the capital holder in order to use their funds for a while.  For a bond, the cost of capital is fixed ahead of time.  For equities, the return/cost is unknown….but it has no upper limit.

The key here is that we have to persuade someone to part with their capital, which means they can’t buy a second home or a boat or anything else.  In a poor society, it’s hard to persuade someone to give up their capital…since the majority of society is struggling to afford the essentials.

But – as wealth increases – people have more capital to play with.  And they’re more easily persuaded to give it up for a while.  Thus, lower cost of capital.  And lower long-term returns for investors.

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